CHANG: Technology has made it easier for all of us to spy on each other. Today we look at one device that's become popular - Amazon's Ring. It's much more than just a doorbell camera. As NPR's Martin Kaste reports, Amazon is marketing the Ring as a safety-centered form of social media.

MARTIN KASTE, BYLINE: This Ring doorbell video is from just a couple of weeks ago. It's a front porch in Richland, Wash., and it's well past midnight.

(SOUNDBITE OF KNOCKING)

KASTE: It's a young man out there - a stranger - and he's talking to himself.

(SOUNDBITE OF ARCHIVED RECORDING)

UNIDENTIFIED PERSON: (Unintelligible) Where's Jesus? Where's he at?

KASTE: Inside the house, Sally Allwine (ph) is frightened. She watches him through the video stream and then talks to him through the app.

(SOUNDBITE OF ARCHIVED RECORDING)

SALLY ALLWINE: What do you want?

UNIDENTIFIED PERSON: Somebody lives here that's a bot.

ALLWINE: What?

KASTE: He sounds confused. And then she tells him there's nobody in this house who knows him. He seems to accept that and drives away. Hours later, before the sun was up, Allwine decided to post a video of the incident. It seemed like the right thing to do.

ALLWINE: Because I think I'm helping my neighborhood. I mean, I don't know he hasn't left here to go someplace else.

KASTE: She posted it to Ring's social media site, which is called Neighbors. It's where people can share videos, photos or just written reports of suspicious activity.

ALLWINE: I felt, as a part of the community, you know, that I should share it. I've read other people, and I do think it's a good tool.

ERIC KUHN: The purpose of Neighbors is really to connect communities around crime and safety issues so they can work to make their neighborhoods safer.

KASTE: That's Eric Kuhn, the general manager of Neighbors. The app is free and open to anybody. You can even use it to upload videos from competing brands of camera.

KUHN: We felt like if you're going to allow communities to connect, you should really allow anyone in the community to connect.

KASTE: Of course, by making the app free and open, Neighbors also functions as a kind of rolling advertisement for Ring, says Matthew Guariglia. He's a policy analyst at the Electronic Frontier Foundation.

MATTHEW GUARIGLIA: That's the brilliant marketing strategy of Ring. Getting on the Neighbors app because you're curious of what's happening in your neighborhood makes it all of a sudden seem like your neighborhood is under siege. There are suspicious people everywhere, behind every fence. And you won't know that, too, until you get a camera.

KASTE: Ring videos tend to look kind of ominous, and any undergrad film studies major can tell you why. First, there's that peephole point of view and then the low position of the doorbell camera, which makes strangers seem to loom large. Guariglia says people should stop and ask themselves how they're affected by this kind of social media.

GUARIGLIA: You see everything uploaded to the Neighbors app through the lens of suspicion and criminal activity, which filters it through our most insidious biases.

KASTE: But even if Ring didn't have Neighbors, it would probably still exist in some form. There are other neighborhood apps, like Nextdoor. And sometimes people even create the networks themselves. That's what happened in the Netherlands, where neighborhood watch groups share photos and videos on WhatsApp. Anouk Mols co-wrote a research paper on this phenomenon, and she found that many people there liked the thought of their neighbors keeping a digital eye out.

ANOUK MOLS: But at the same time, sometimes even the same respondents were also very ambivalent about this because they said, it makes me more anxious to be aware of all the things that are happening. It simultaneously makes people feel safer, as well as more anxious.

KASTE: She says some Dutch police participate in the local WhatsApp groups, while others prefer not to. Here in the U.S., Ring offers police departments a way to see videos that people in a certain area have chosen to post or to send out requests for videos that might be close to an incident they're investigating. So far, only a small percentage of departments have signed up for this.

Micah Lundborg is chief of police in Edgewood, near Tacoma.

MICAH LUNDBORG: This is just another tool in the toolbox for us in terms of making things a little easier in terms of legwork for certain crimes.

KASTE: He also cautions people against spending too much time on the app watching videos, in his words, building a wall of concern.

There are also some reasons to think twice before posting videos. Back in Richland, Wash., Sally Allwine now regrets the video that she posted of that young man on her front porch because it turns out that later that same night, he was killed in a confrontation with sheriff's deputies. In the aftermath, her video of him on the porch quickly spread to the larger Internet, and she was dismayed by the unkind comments that it attracted about that young man.

ALLWINE: Everybody just was stupid. Like, nobody has any compassion for anybody. All I wanted to do is give everybody a heads-up that this person is out and about, and I have lived to regret it.

KASTE: She's still glad that she has the camera. But next time it captures a scene like that, she says she will not be posting it.